Time fuse



Dec. 31', 1940.

G. PERRENOUD TIME FUSE Filed Dec. 27, 1937 Q Erre/youd Patented Dec. 3l, 1940 PATENT OFFICE TIME FUSE Georges Perrenoud, Le Locle, Switzerland Application December 27, 1937, Serial No. 181,923 In Switzerland January 30, 1937 Z Claims.

This invention relates to a new and improved regulating mechanism for the clockwork of mechanical time fuses designed for artillery projectiles.

Heretofore upon the firing of a projectile the pendulum controlling the clockwork exerted a relatively great tractional force upon the regulating spring for the clockwork and the other rather small associated elements which was liable to cause a breakage of the regulating spring. Such action would also produce a fatigue in the spring destroying the elastic properties thereof. Furthermore due to such force the sleeves suspending the spring might slide with relation thereto 165' and thus modify the active or effective length of the spring. Also such force was liable to cause a sliding of the pendulum shaft in the connection provided between the pendulum and the regulating spring and thereby modify the oscillating period of the pendulum. It is an object of the invention to correct the above defects.

It is a further object of the invention to associate a shock absorbing means with the regulating spring so as to protect such spring particularly at the moment of firing when the acceleration is the greatest.

A further object of the invention is to provide means to counteract the effect of the shock upon the torsion spring extending along the axis of the projectile upon the firing of the projectile and also to protect such spring from the strain imposed thereon due to the weight of the pendulum itself.

A further object of the invention is to provide a resilient support for both the torsion spring and the pendulum support thereby.

A further object is to provide means whereby all strain is removed from the regulating spring.

With these and other objects in view which will become apparent as the description proceeds the invention consists in the combination of elements hereinafter described in detail, claimed in the claims and shown in the drawing in which- Fig. 1 is a cross sectional view of the head of a projectile with the body thereof shown only partially.

Fig. 2 is a plan view of a detail.

Referring to the drawing in which similar reference characters are used to indicate like elements 50 the pendulum is shown at I and the regulating spring formed as a torsion spring and consisting of a steel wire, for example, is shown at 2. The clockwork for the fuse has been omitted from the drawing since the invention has reference 56 only to the regulating mechanism therefor.

'I'he pendulum I and the regulating spring 2 extend along the axis of the projectile whose conical shell head is shown at 3. The lower pivot of the pendulum is mounted in the body 4 of the projectile on which the head 3 is screw threaded. The upper pivot for the pendulum is seated in a dulum I is located. The plate 8 is connected to the body 4 of the projectile by means of the screws II of which only one is shown on the drawing'. The shaft of the pendulum extends through a bore I2 provided in the plate 8 and an upper bearing I3 and a lower bearing I4 is provided for such a shaft. These bearings I3 and I4 and the opening below the lower end of the bearing I4 which will permit adjustment of the lower pivot of the pendulum shaft allow the pendulum and the sleeve 5 a certain amount of movement or axial play which is limited by the lower surface of the recess 9 and the lower surface oi' the plate 8.

The torsion or regulating spring 2 is connected at its lower end to the sleeve member 5 and at its upper end to the cylindrical sleeve member 5. The sleeve member 5' is located in an opening, which is preferably circular, of the member I5 which may have any desired shape. The member I 5 is mounted upon the upper end of the protecting tube I6 which is secured in any desired way to the socket member 1. At about the central portion of the protecting tube I6 for the torsion spring 2 there is provided a washer member I1 having a central aperture which assists in guiding the spring.

As is obvious from the construction above described the sleeve, members 5 and 5' are capable of movement along the longitudinal axis of the projectile. The sleeve member 5 may have such movement in the recess 6 provided in the socket member 1 while the sleeve member 5' is capable of such movement in the opening provided in the member I5.

The support for the sleeve member 5 consists of a shock absorbing spring I8 which is secured to the member I5 by rivets or any other desired securing means. The spring I8 may be star shaped, for example, and is secured at its central portion to the sleeve member 5'. As is obvious any other desired type of resilient mounting for the sleeve member 5' may be utilized in order to permit the sleeve member 5' to have limited axial movement relative to its support extending between the bearing 20 and a bar 2| the member I5.

'I'he spring I8 normally holds the sleeve member in its upper position as shown in the drawing in which the sleeve member 5' bears against the lower surface of the bar 2| It naturally follows that the regulating spring 2 and the pendulum I associated therewith are normally suspended from the sleeve member 5' which is held in itsV uppermost position by the action of the shock absorbing spring I8. However upon firing the projectile and the subsequent great acceleration given to the projectile body, the penmounted on dulum due to its inertia will Withdraw the sleeve, member 5 from the bar member 2l against the action of the spring I8 thereby materially re-v ducing the force of the shock upon the torsion spring itself.

As a further safeguard the axial play of the sleeve member 5 is preferably greater than that of thependulum I sot that upon ringthe torsion spring maybe completelyrelieved from the consequent shOCk. during the initial axial accelerationof theiDIOjCtile. f

the' acceleration ceases the4 various members ofv the regulating mechanism willy gradually resume their original or normal position through the.v action of the springljl 8; andthe pendulum Will thenl beginl to oscillate.

As will benoted from the construction described when thel pendulumv is: in4 operation the sleeve member 5 andthe bearings I-3 and IIIl of the pendulunl;v shaft are not in Contact with any other frictional'surface since the entire regulating system is suspended from the sleeve member 5'. From thisv construction it follows that the elements off theregulating system will function unjder the bestpossible conditions and With the elimination ofv practically all` friction.l

.49 'IhreT aboveA described embodimenty is a preferredA construction which is given byway of example only since it is obvious that the invention may be modied Within rather Wide limits without departing from the gist of the invention. Although in practice the shock absorbing means are formed by one or more springs of various types these means may also include or' comprise any resilient or elastic element which is suitable for and capable of accomplishing the functions of` a shols abserber. F01?, example, Such Shock absorbing effect may be obtained by mounting the protective tube I6 resiliently in an axial direction.

I claim:

l. A regulating mechanism for the clockwork of a mechanical time fuse for projectiles comprising a pendulum, a torsion regulating spring located along.v the longitudinal axis of the projectile supporting said pendulum, a protecting tube eneirrfclinugv said spring, a support for said spring at its forward end, a shock reducing spring supporting Said, Support located: uson: the. forward end of saidprotecting tube, a coupling member connectingy the rear end offsaid regulating spring to the axis of said pendulum and said pendulum beine disposqdvfin, the bodyof said projectile with relatively Slight anal playj 2. Axeeulatng: mechanism for the: clockwork of a mechanical time ffuse fon ptojectilescomprising a pendulum, a torsion,l regulating spring located along the longitudinal axisA of the projectilesupporting said pendulum, a protecting tube encircling said.- spring, a support for said spring at its forwardy end, a star shaped. shock reducing spring supporting. said; support located; upon the forward end of said;- protecting tube, a coupling member connecting the rear end ot said-regulating spring to the axis of= saidpendulum'andl said pendulum being disposed in the body or said projectile with relatively slight axial play.

GEQRGES'. PERRENOUD. 

